Conventionally, nuts are screwed onto threaded shafts at the end of the shaft. Repeated rotation of the nut causes the nut to move along the shaft to its final desired position. Sometimes this process is not possible. The shaft may run between two pieces, resulting in no available end for the placement of a nut. Also, damage to the threads prevents the entry of the nut on the end of the shaft.
It is often advantageous to be able to place a nut anywhere along the length of a threaded shaft. The prior art discloses split nuts which may be placed about a threaded shaft. One such disclosure is found in U.S. Pat. No. 2,664,023 (Mugford). Mugford discloses a snap-on split nut having two halves connected by a hinge 32. U.S. Pat. No. 4,657,458 (Woller et al.) discloses an anchor nut for a threaded member having two halves connected together by a thin flexible web or hinge 28 enabling the two sections to be moved from an unfolded position to a folded position. U.S. Pat. No. 5,039,266 (Nagayoshi et al.) discloses a divided nut, having two halves connected together by a hinge 9 or connected by a bayonet coupling.
Split nuts using thin flexible hinges suffer from several problems. Repeated use of the nut will cause metal fatigue in the hinge and eventual breakage. Also, during transportation or use, a hinge may easily become bent or twisted preventing the alignment of the two halves of the nut. Misalignment of the nut causes a misalignment of the threads rendering the nut unusable. Also, the flexible hinge often protrudes outside the perimeter of the nut preventing the application of a tool used for tightening. Other prior art devices, such as disclosed in U.S. Pat. No. 4,572,032 (Kinzler), U.S. Pat. No. 4,132,146 (Uhlig), U.S. Pat. No. 1,803,888 (Basola et al.) and U.S. Pat. No. 6,206,620 (Burns) disclose nuts and dies having hinges more substantial than a thin web of material. These hinges increase the manufacturing cost of the nuts and makes these nuts less likely to be bought and used.